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Anti-renal cell carcinoma (RCC) agents with new mechanisms of action are urgently needed. Twenty-seven natural products of the piericidin class, including 17 new ones, are obtained from a marine-derived Streptomyces strain, and several of them show strong inhibitory activities against ACHN renal carcinoma cells. By exploring the mechanisms of two representative natural piericidin compounds, piericidin A (PA) and glucopiericidin A (GPA), peroxiredoxin 1 (PRDX1) is detected as a potential target by transcriptome data of PA-treated ACHN cells, as well as the paired RCC tumor versus adjacent nontumor tissues. PA and GPA induce cell apoptosis through reducing the reactive oxygen species level caused by upregulated PRDX1 mRNA and protein level subsequently and exhibit potent antitumor efficacy in nude mice bearing ACHN xenografts, with increasing PRDX1 expression in tumor. The interaction between PA/GPA and PRDX1 was supported by the docking analysis and surface plasmon resonance. Moreover, the translocation of PRDX1 into the nucleus forced by PA/GPA is proposed to be a key factor for the anti-RCC procedure. Piericidins provide a novel scaffold for further development of potent anti-RCC agents, and the new action mechanism of these agents targeting PRDX1 may improve upon the limitations of existing targeted drugs for the treatment of renal cancer.

Background Radiotherapy after breast-conserving surgery (BCS) is not always necessary in older women staged T1N0M0 with low-risk invasive breast cancer, but few studies have concluded the detailed tumor size as a reference for avoiding radiotherapy. The study was conducted to explore and identify the optimal cutoff tumor size. Methods The study population was from the Surveillance, Epidemiology, and End Results (SEER) database in 2010–2016. Propensity score matching was used to balance the confounders between groups. Predictors associated with survival were analyzed by Kaplan–Meier, X-tile, Cox proportional hazards model and competing risk model. Results A total of 52049 women and 3846 deaths were included in the cohort with a median follow-up of 34 months. Based on the cutoff value determined by X-tile analysis, the study population were divided into small tumor group (≤14 mm in diameter) and large tumor group (>14 mm in diameter). Small tumors and radiotherapy were correlated with better breast cancer-specific survival (BCSS). In subgroup analysis, the absolute benefit of BCSS in 6 years attributed to radiotherapy was only 0.90% (RT vs. non- RT:98.77% vs. 97.87%) for patients with small tumors but up to 3.33% (RT vs. non- RT:97.10% vs. 93.77%) for those with large tumors. Conclusion Small tumors and adjuvant radiotherapy were associated with improved long-term prognosis, and 14 mm in diameter was the cutoff tumor size of omitting radiotherapy for patients aged 65 or older with T1N0M0 stage, ER+ and HER2-breast carcinoma after BCS., Graphical abstract Image 1, Highlights • Breast tumor size of 14 mm was the optimal cutoff predicting OS and BCSS. • Small tumors (≤14 mm) and radiotherapy were associated with improved OS and BCSS. • The benefit of radiotherapy was significant in patients with large tumors (>14 mm). • Radiotherapy could be omitted in elders with small low-risk breast tumor after BCS.

The mangrove-sediment-derived actinomycete strain Streptomyces&nbsp, psammoticus SCSIO NS126 was found to have productive piericidin metabolites featuring anti-renal cell carcinoma activities. In this study, in order to explore more diverse piericidin derivatives, and therefore to discover superior anti-tumor lead compounds, the NS126 strain was further fermented at a 300-L scale under optimized fermentation conditions. As a result, eight new minor piericidin derivatives (piericidins L-R (1–7) and 11-demethyl-glucopiericidin A (8)) were obtained, along with glucopiericidin B (9). The new structures including absolute configurations were determined by spectroscopic methods coupled with experimental and calculated electronic circular dichroism. We also proposed plausible biosynthetic pathways for these unusual post-modified piericidins. Compounds 1 and 6 showed selective cytotoxic activities against OS-RC-2 cells, and 2–5 exhibited potent cytotoxicity against HL-60 cells, with IC50 values lower than 0.1 μM. The new piericidin glycoside 8 was cytotoxic against ACHN, HL-60 and K562, with IC50 values of 2.3, 1.3 and 5.5 μM, respectively. The ability to arrest the cell cycle and cell apoptosis effects induced by 1 and 6 in OS-RC-2 cells, 2 in HL-60 cells, and 8 in ACHN cells were then further investigated. This study enriched the structural diversity of piericidin derivatives and confirmed that piericidins deserve further investigations as promising anti-tumor agents.

Reported as two antirenal cell carcinoma (RCC) drug candidates, marine-derived compounds piericidin A (PA) and glucopiericidin A (GPA) exhibit hepatotoxicity in renal carcinoma xenograft mice. Proteomics and transcriptomics reveal the hepatotoxicity related with cholesterol disposition since RCC is characterized by cholesterol accumulation. PA/GPA aggravate hepatotoxicity in high-cholesterol diet (HCD)-fed mice while exhibiting no toxicity in chow diet-fed mice. High cholesterol accumulation in liver is liver X receptor (LXR)-mediated cytochrome P450 family 7 subfamily a member 1 (CYP7A1) depression and low-density lipoprotein receptor (LDLR) activation. The farnesoid X nuclear receptor (FXR) is also depressed with a downregulated target gene OSTα. Different from PA directly combined with LXRα as an inhibitor, GPA exists as a prodrug in the liver and exerts toxic effects due to transformation into PA. Surface plasmon resonance (SPR) and docking results of 17 piericidins illustrate that glycosides exert no LXRα binding activity. A longer survival time of GPA-treated mice indicates that further exploration in anti-RCC drug research should focus on reducing glycosides transformed into PA and concentrating in the kidney tumor rather than the liver for lowering the risk of hepatotoxicity.

BACKGROUND: Cancer will become the leading cause of death worldwide in the 21st century, meanwhile, immunotherapy is the most popular cancer treatment method in recent years. COPI Coat Complex Subunit Beta 1 (COPB1) relates to human innate immunity. However, the role of COPB1 in pan-cancer remains unclear. OBJECTIVE: The purpose of this study was to explore the relationship between COPB1 mRNA expression and tumor infiltrating lymphocytes and immune examination sites in pan-cancer. METHODS: Data from multiple online databases were collected. The BioGPS, UALCAN Database, COSMIC, cBioPortal, Cancer Regulome tools, Kaplan-Meier Plotter and TIMER website were utilized to perform the analysis. RESULTS: Upregulation of COPB1 has been widely observed in tumor tissues compared with normal tissues. Although COPB1 has poor prognosis in pan-cancer, COPB1 high expression was beneficial to the survival of ESCA patients. Unlike ESCA, COPB1 expression in STAD was positively correlated with tumor infiltrating lymphocytes, including B cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells. Finally, we also found that the expression of COPB1 in STAD was positively correlated with PD-L1 and CTLA4. CONCLUSIONS: COPB1 may be a prognostic biomarker for pan-carcinoma, and also provide an immune anti-tumor strategy for STAD based on the expression of COPB1.

A pair of novel lipopeptide epimers, sinulariapeptides A (1) and B (2), and a new phthalide glycerol ether (3) were isolated from the marine algal-associated fungus Cochliobolus lunatus SCSIO41401, together with three known chromanone derivates (4–6). The structures of the new compounds, including the absolute configurations, were determined by comprehensive spectroscopic methods, experimental and calculated electronic circular dichroism (ECD), and Mo2 (OAc)4-induced ECD methods. The new compounds 1–3 showed moderate inhibitory activity against acetylcholinesterase (AChE), with IC50 values of 1.3–2.5 μM, and an in silico molecular docking study was also performed.

Three new eremophilane sesquiterpenes, dendryphiellins H-J (1-3), and three new phthalide natural products (4-6) were isolated from the marine-derived fungus Cochliobolus lunatus SCSIO41401. Their structures including absolute configurations were determined by spectroscopic and calculated ECD analyses. Dendryphiellin I (2) showed cytotoxic and antibacterial activities against five cancer cell lines (IC50 1.4 to 4.3 μM) and three bacterial species (MIC 1.5 to 13 μg/mL), respectively. Dendryphiellin J (3), a rare naturally occurring aldoxime analogue, displayed cytotoxicities against ACHN and HepG-2 cells with IC50 values of 3.1 and 5.9 μM, respectively. Further studies indicated that 3 induced apoptosis in ACHN cells in a dose- and time-dependent manner.

Two novel sorbicillinoid adducts containing bicyclo[2.2.2]octane and tetrahydrofuran moieties, named sorbicillfurans A and B (1 and 2), were isolated from the static culture of the marine-derived fungus Penicillium citrinum SCSIO41402. Their structures including absolute configurations were determined by spectroscopic and calculated ECD analyses. Sorbicillfurans A and B (1 and 2) are the first examples of sorbicillinoids possessing a tetrahydrofuran unit. In the proposed biosynthetic pathway, sorbicillfuran B (2), harboring a rare and complex polycyclic framework, is probably formed by two Diels-Alder reactions. Both isolates were evaluated for the cytotoxicity against six human cancer cell lines, only sorbicillfuran B (2) showed weak cytotoxicity against HL-60 cells with an IC50 value of 9.6 μM.

Iakyricidins A-D (

A new spirocyclic γ-lactam, named spirostaphylotrichin X (1), and three related known spirostaphylotrichins (2-4) were isolated from the marine-derived fungus Cochliobolus lunatus SCSIO41401. Their structures were determined by spectroscopic analyses. Spirostaphylotrichin X (1) displayed obvious inhibitory activities against multiple influenza virus strains, with IC50 values from 1.2 to 5.5 μM. Investigation of the mechanism showed that 1 inhibited viral polymerase activity and interfered with the production of progeny viral RNA. Homogeneous time-resolved fluorescence, surface plasmon resonance assays, and a molecular docking study revealed that 1 could inhibit polymerase PB2 protein activity by binding to the highly conserved region of the cap-binding domain of PB2. These results suggest that 1 inhibits the replication of influenza A virus by interfering with the activity of PB2 protein and that 1 represents a new type of potential lead compound for the development of anti-influenza therapeutics.

Marine micro-organisms in the deep-sea hydrothermal vent systems are considered as potential sources of bioactive natural products. Sixteen bacterial strains were isolated from a deep-sea hydrothermal field and screened for bioactive metabolism studies. After the strains were subjected to bioactive testing at different culture media, chemical dereplication by HPLC coupled to high-resolution mass spectrometer was performed to analyse or determine the main secondary metabolisms in those strains. Strain 06204 was large-scale fermented with relative optimal media, for isolating the desired sulphur compound. Butyrolactone I 3-sulphate was isolated and structurally identified from the extract, guided by dereplication and showed moderate antivirus activities against H3N2 and EV71 viruses. Our study suggests that deep-sea hydrothermal bacteria are good sources of sulphur natural products. Meanwhile, the described approach, mainly bioactive screening, dereplication and targeted isolation, is effective and efficient to discover interesting bioactive compounds in hydrothermal bacteria.